Chich expression correctly describes force using Sl units

calculate the diameter of a silver wire of length 75cm , which is extended by 1.85mm when a 10kg mass is suspended from it's end

sdas [7]

Answer: $0.8\ mm$

Explanation:

Given

length of wire $l=75\ cm$

change in length $\Delta l=1.85\ mm$

mass of wire $m=10\ kg$

Young's modulus for silver $E=7.9\times 10^{10}\ N/m^2$

load on wire $F=mg$

$F=10\times 9.8=98\ kg$

change in length is given by

$\Delta l=\dfrac{Pl}{AE}$

Where A=area of cross-section

$A=\dfrac{Pl}{\Delta lE}$

$A=\dfrac{98\times 0.75}{1.85\times 10^{-3}\times 7.9\times 10^{10}}$

$A=\dfrac{73.5}{14.615\times 10^{7}}$

$A=5.029\times 10^{-7}\ m^2$

also wire is the shape of cylinder so cross-section is given by

$A=\dfrac{\pi d^2}{4}=5.029\times 10^{-7}\ m^2$

$\Rightarrow d^2=\dfrac{5.029\times 10^{-7}\times 4}{\pi }$

$\Rightarrow d^2=64.02\times 10^{-8}$

$\Rightarrow d=8\times 10^{-4}\ m$

$\Rightarrow d=0.8\ mm$

4 0

3 years ago

What’s happening to the car’s motion?

ExtremeBDS [4]

Answer:

It returned to where it had started at the end of the trip

Explanation:

5 0

3 years ago

Read 2 more answers

The first moment of the total cross-sectional area taken about the neutral axis must be?

bekas [8.4K]

The first moment of the total cross sectional area taken about the neutral axis must be zero.

As with non-composite beams, the neutral axis (NA) is the location where the bending stress is zero. The location of the NA depends on the relative stiffness and size of each of the material sections.

Generally, the NA location is determined relative to the bottom surface of the beam. However, this is not mandatory, and the location can be relative to any location. If the bottom is used, then the NA axis is a distance "h"

The distance h can be determined by recalling that the stresses through the cross section must be in equilibrium.

learn more about neutral axis from here: brainly.com/question/28167877

#SPJ4

7 0

2 years ago

Read 2 more answers

What is the direction of the force for a negative charge moving downward in a magnetic field pointing to the left? out of the sc

AveGali [126]

It would be towards your side. Right hand thumb rule

4 0

3 years ago

A research submarine has a 30-cm-diameter window that is 8.6cm thick. The manufacturer says the window can withstand forces up t

Triss [41]

What is missing is the density of salt water. Let's denote it ρ.
The pressure at depth d then is: 
p = p0 + ρ g d 
, where p0 is the atmospheric pressure at the surface of the sea. We assume it is equal to the 1 atm inside the sub. 

Hence the pressure difference between inside and outside of the window is: 

Δp = ρ g d 

The force on the window is this pressure difference, multiplied by the area of the circular window of diameter D. The latter equals 
A = ¼ π D². 

So 
F = p A = ¼ π D ²ρ g d. 
This should be less than Fmax. 

Hence d < Fmax / (¼ π D ²ρ g ).

6 0

3 years ago